Adjustable cutter bar



Feb, 15, 1944.

J. N. FIELDS ADJUSTABLE CUTTERKBAR Filed- Sept. 6. 1941 A Psieniedreb. 15,1944

" UNITED STATES iuiTiezNT` oi-Ficia K snms'rsirlgili'rsa aan I Y sppiiestzri srzai. itam icisim. roi. iss-294) is und |s. The purpose ef the luge n and u and the pins II and II will be set forth inlhore 'I'his invention relates to lawn mowers and more lglrticularly to au improved adjustable cutter ne object of the invention is to provide an adJu'stablecutter bar which will, during the operation of the lawn mower.- shift away from the cutting reel upon contact with a stick, nail, piece of wire, or other obstruction, so that danger'of bending, breaking, or dulling of the cutter -bar will be practically eliminated.

Another object of the invention is to provide an adjustable cutter bar which will shift away from the reel upon encountering.an obstruction so that nicking of the blades of the reel'will be largely prevented.

A further object of the invention is to provide a device of this ter which may be easily installed and remov Still another object of the invention to prof' vide acutter bar whichmay b'e readily adjusted with lrespect to the reel so that maximum cut-v ting elciency in be had at all times.

'Still further ob ects of the invention, not spe- "ciilcally mentioned hereinbei'ore, will become apparent during the course .of the following description. v :l the drawing forming a part-of my applicaon: v

Figure 1 is a longitudinal sectional view of a lawn mower equipped with my improved adjustable cutter bar,

Figure 2 is a transverse sectional; view on the lineZ-IoiFigureLand Figure 3 is a detail sectional view' showing the eutter bar as it would appear ener being shifted away from the reel by contact with a stick.

In the drawing like numerals of reference designate like parts throughout theviews. v

v'll'he numeral Il indicates in general al lawn mower or conventionaldesign. The lawn mower I includes wheels 2. a frame l and a reel I, said reel being of conventional design and including blades I. The frame. l includes 'side plates I detail hereinafter. Extending-longitudinally of the side plates I and 1 medially of their heights and beneath the lugs I3 and I4, respectively, are inwardly directed webs I1 and I8. i

As -best seen in Figure 2, the side plates G and 1 are formed with bosses which are apertured to define bearings is and 20. My improved cutter bar extends between the side plates I and 1 and includes trunnions 2l and 22) which are joumaled in the bearings I! and 20, respectively. 'Ihe cutter bar, as indicated in general by the numeral 2l, comprises a cutter plate 24 having a cutting edge 25. The cutter 'plate 24 is turned up at its rear portion to denne a reinforced rib ZI, and at its opposite ends, the cutter bar is formed with upstanding ilanges 21 and 23, said flanges carrying the trunnions 2I and 22.- respectively, and

being formed with ilat straight upper surfaces 2l'.-

As will beV noted, the nions 2lv and 22 are located substantially d-way of the length 'of -the flanges so that the cutter bar will be -balanced in its mounting between the side plates I and -1. VThe cutting edge Il is, ofcourse, disposed to cooperate. with the-cutting edge of each of the blades I of the reel so that, when blades of grass are confined between the cutting edge ZI and the cutting edges oi.' the blades I, selectively, said blades of grass will be severed, in

Ithe conventional manner.

Threaded in the webs I1 and Il, near their corresponding forwardends. areset. screws 3l, said' set screws having their corresponding lower ends contacting theforward end portions of the ilat surfaces Ilot the flanges 21 and Il. Freely mounted within openings of the web; I1 and and 1 which extend rearwardly of the lawn mower Y iustably `connect the roller mounting plates l and Ito the frame;

`On the side plates I and 1, medially oftheir lengths and on their corresponding upper edges.

Formednthe lugs Il and 1I, respectively. and

v i nl Ilare springs Il and I3, the spring I! extending through the web I1 and the spring Il extendingthroughtheweb Il. Aswillbeseemthe corresponding upper ends of the springs are anchored against the lugs I3 and I4 by the centering pins II and II. The corresponding lower ends of the springs Iland Il bear against the flat surfaces of lthe flanges 21 and Ilv respec.

. v tively, near the corresponding rear ends of said "earegformgdinwardly directed lugs I8 and il.

y depending therefrom are integral centering Apins ilat surfaces and rearwardlyof the trunnions Y2| and 22. The springs II and Il normally urge the rear end ofthe cutter bar downwardly so that the forward ends of the flanges will abut the set screws 8l. The set screws 8l are, of course, adjusted forsupporting the cutting edge -II-in a proper Position with respect to the blades I of the reel l.

In use, the mixer ilwiu'si-st be diurne :er

positioning the cutter' ser ze a desired height abo'vethe ground. As the lawn mower is moved loverthe ground, the reel will rotate and the tact with the cutter bar. said cutter bar will rock on the trunnions 2| and 22 and against thetension of the springs 32 and 3l to the position shown in Figure 3, for allowing .the stick either to pass between the blade of the reel and the cutter bar or to be dislodged from between said reel blade and cutter bar. linany event, rock-v ing oi the cutter bar away from the reel will prevent nicking of the blade of the reel and also will prevent damage to the cutting edge of the cutter bar or to the cutter bar as a whole. The set screws 30 provide an abutment so that. when -the obstruction has been dislodged, the cutter bar will return to normal operative position. The cutter bar may be adjusted simply by rotating the set screws and rocking said cutter bar on the trunnions 2l and 22. Downward movement o! the set screws will, of course, rock the cutter bar against'the tension of the springs t2 and 32 and will shift the cutting edge 25 away from the reel. when the set screws are rotated in.- the opposite direction, they will move upwardly within the webs i1 and i8. When this takes place. the springs 32 and 33 will rock thecutter bar for moving the cutting edge 25 toward the reel I.

lt is believed that, by. the use of my improved cutter bar, increased eilcieney in the operation` of a lawn mower will be secured. The construction hereinbei'ore described is characterized by the utmost simplicity. Also, as will be apparent, the'device may be readily installed and removed from the lawn mower when desired. It is thought that the construction and operation of my improved cutter bar will now be thoroughly understood.

v.asuma y Having thus described the invention. what is claimed as new is:

A lawn mower having a trame provided with side plates, said side plates being formed with intermediate longitudinally disposed inwardly extending reiniorcing webs having their upper edges provided with overhanging lugs spaced vertically from said intermediate webs and provided with depending centering pins, there being openings formed in' the webs and vertically alined with the centering pins, said sideplates beneath the intermediate webs being provided with apertured bosses to form bearings, a reel carried by the frame `and having blades each formed with a cutting edge, a cutter bar having a cutter plate formed with a cutting edge. said cutter bar having upstanding end ilanges formed with trunnions Journale-d in said bearings and provided with an upturned reinforced rear portion. said flanges having upper dat edges. set screws threaded in the intermediate webs and engageable with the flat upper edges o! the flanges at one side ci the trunnions for positioning the cutting edge o! the cutter plate to cooperate with the cutting edges oi the reel blades for eilecting a cutting operation upon rotation of the reel and movement ot the lawn mover over a lawn, and springs extending through the openings in the intermediate webs and fitting around the centering pins, the lower ends of said springs engaging the fiat upper edges o! the ilanges of the cutter bar near the rear ends'ol the anges, said springs urging the cutter bar into engagement with the set screws and said cutter bar being movable against the tension of the springs for separating the cutting edge of said bar from the cutting edge of the adjacent reel blade upon engagement with an obstruction for preventing vdamage to the cutting edge of the cutter bar and the cutting edge of the reel blade.y

JOY N. limbs. 

